The NoName map layer used to be available on the openstreetmap.org front page as an alternative layer. It highlighted roads which had no name=* tag (At the time these tended to be those roads which had been traced in from imagery through armchair mapping, rather than having been surveyed at all)

NoName tag

We can distinguish a road where the name is unknown and a road which has really no name.

noname=yes can be used to mark the absence of a name i.e. where something really does not have a name in reality.

CloudMade's original map

For several years a noname map was provided by CloudMade. This was included on the OpenStreetMap.org front page (Featured tiles).

It showed red casing at higher zoom levels, or as thin red lines at lower zoom levels. After being removed from the openstreetmap.org homepage, it remained available a maps.cloudmade.comfor rendered as part of their style-editor infrastructure for a time. That's all no longer available.

South East London as it was back in 2008 showing many missing road names. The NoName map was a useful guide for planning events like the London Mapping Party Marathon, allowing quick identification of areas that were traced from aerial images, but where road names were missing

At closer zoom levels the NoName was useful for identifying individual streets that had been missed